Advancement in semiconductor technology is often limited by semiconductors' limited life span. Specifically, a semiconductor system suffers from gradual or abrupt failures due to aging. Along these lines, accumulated quantum mechanical effects cause semiconductor device failure even under nominal operation conditions. Such failure dramatically degrades system performance and reliability. Previous approaches provide estimated life span only. That is, previous approaches attempt to predict the reliability of device technology and publish it as a specification. Such an approach, however, is not useful to measure individual chip aging since: it does not experience circuit switching behaviors; it does not imitate system operation pattern in practice; and it requires high precision data converters.
The following previous attempts have been made:
U.S. Pat. No. 7,592,876—This patent discloses a method for monitoring the age of a target circuit component in a semiconductor device by using at least one aging leakage oscillator and a reference leakage oscillator. The aging oscillator is stressed whenever the target circuit component is used while the reference oscillator is not.
U.S. Pat. No. 7,495,519—This patent discloses a system and method for monitoring reliability of a digital system and for issuing a warning signal if the digital system operation degrades past a specific threshold. The technique utilizes a ring oscillator sensor in association with the digital system, wherein logic and/or device percent composition of the ring oscillator sensor mirrors percent composition thereof within the digital system.
U.S. Pat. No. 7,307,328—This patent discloses a semiconductor body in which is integrated a temperature sensor for measuring the temperature in the semiconductor body. Reducing the amount or occurrence of thermal damage to a semiconductor device is the object of this invention.
U.S. Pat. No. 7,283,919—This patent discloses a system that tests the quality and/or the reliability of a component by applying test conditions to a plurality of specimens of the component during operation.
U.S. Pat. No. 6,662,142—This patent discloses a system for providing information on quality and reliability of optical semiconductor devices by using a communications network.
U.S. Patent Application 20060049886—This patent application discloses an on-die record-of-age circuit which includes a reference oscillator circuit, an aging oscillator circuit, and a frequency comparator.
U.S. Pat. No. 7,340,359—This patent discloses a method for augmenting quality or reliability of semiconductor units, including providing semiconductor units that are subject to quality or reliability testing.
U.S. Pat. No. 6,414,508—This patent discloses a method for predicting reliability of semiconductor devices and wafers without a lengthy burn-in process. A set of electrical tests are performed before and after stressing each of the semiconductor devices with an elevated voltage above normal operating voltage for the semiconductor device.
U.S. Pat. No. 4,520,448—This patent discloses a method of characterizing reliability in bipolar semiconductor devices. A reliability function is determined as a function of the interface charge density, the oxide charge density, and the impurity concentration in the epitaxial silicon layer and is correlated with a time-to-fail.
U.S. Patent Application 20100109005—This patent application discloses a semiconductor device from which electrical measurement data may be obtained for enhanced spatial resolution by providing a distributed sensor structure.
U.S. Patent Application 20090237103—This patent application discloses a semiconductor die including a semiconductor chip and a test structure located in a scribe area.
However, none of these previous attempts provide an accurate way to truly model the age of semiconductors and/or functional blocks thereof. In view of the foregoing, there exists a need for a solution that solves one or more of the deficiencies of the related art.